The NationalDNA edits of embryosMar 26, 2015 | 2:35Prominent scientists warn it's time for a moratorium on powerful new genetic engineering tools that can add and remove genes from sperm, eggs or human embryos

The NationalVirgin Galactic spaceship crashesOct 31, 2014 | 2:28A Virgin Galactic spaceship crashed during a test flight in California. One of the two pilots on board was killed, the other seriously injured.

The NationalCelestial equivalent of a near collisionOct 19, 2014 | 1:46A four-and-a-half billion year old comet passed by Mars today with a fleet of sophisticated spacecraft capturing every moment of it.

The NationalChris Hadfield on taking photos from spaceOct 17, 2014 | 10:48Canadian astronaut Chris Hadfield talks with Wendy Mesley about his photographs from space, the earth and what earthlings should worry about.